if
If in doubt, explain the situation in front of the courier, take photos and indicate the reasons on the list. If you don't sign, you will refuse to sign, and the goods will be returned.
Generally, Taobao merchants will not admit that the courier left after receiving the goods. This common problem is fragile goods. For fragile goods, it's best to ask the courier to wait for your inspection before leaving.
For the wrong goods, or defective goods, contact the merchant in time, and the merchant will basically solve it.